JPH0363097A - Controller for washing machine - Google Patents

Abstract

PURPOSE:To detect the turbidity change of washing solution exactly and enable washing or rinsing operation to be controlled by arranging a light emitting element and alight receiving element arranged near a drain valve, and a control means for determining the driving current of the light emitting element after the drain valve is turned ON for a specified time under feeding the water of the rinsing operation. CONSTITUTION:At the time of a first rinsing, a feed water valve 12 is turned ON by a microcomputer 24 and water is fed to the lowest water level. After that, a drain valve 10 is turned ON for three seconds for draining. This is for discharging bubbles generated at the time of dehydration in a previous process, from a transmission rate detecting section 13. Then a PWM data for determining the driving current If of a proper light emitting element 13a so that output voltage V1 may be always changed in an active area, is set when water is pure in the transmission rate detecting section 13, and the output voltage V1 is set to be VW. The determined data is written into a nonvolatile memory 25 in order to use the data at the time of following washing. When water is fed to a specified water level after said operation and rinsing control is started, the turbidity of washing solution to the pure water at the time of the saturation of sensor output voltage can be exactly detected, and proper washing operation according to the dirty degree of the washing can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a washing machine control device that optically detects the degree of contamination of liquid in a tank and automatically performs washing cabinet or rinsing operation. It is something.

Prior Art Conventionally, as a control device for this type of washing machine, Japanese Patent Application Laid-Open No. 61-5
There is a force 5 shown in Publication No. 0595.

That is, a washing machine control device has been proposed that is equipped with a dirt level detector that optically detects changes in the turbidity of the washing liquid and automatically performs washing or rinsing operations based on the output data of the dirt level detector. ing.

This washing machine control device includes a light-emitting element and a light-receiving element that are arranged at the inner bottom of the water receiving tank so as to face each other across the internal water, and generates an amount of output that depends on the amount of light irradiated from the light-emitting element. A dirt level detector is configured with the light receiving element.
Washing times are determined based on changes in the transparency of washing water compared to clean water during agitation, and the laundry is divided into ``large,'' medium, and small stains.

Problems to be Solved by the Invention However, in the above-mentioned washing machine control device, the surface of the light emitting element and light receiving element may be damaged by dirt from the laundry, detergent left undissolved during washing, water scale, etc. When the light receiving element becomes dirty, the output of the light receiving element is lower than when it is dirty. In other words, even if the laundry is not dirty, if the surfaces of the light-emitting element and light-receiving element are dirty, the transparency of the washing water compared to fresh water will be lower, so there is a problem that the laundry will be judged as heavily soiled and the washing time will be longer. Ta.

Therefore, the present invention solves the above-mentioned conventional problems, such as dirt adhering to the surface of the light emitting element button and light receiving element, and dirt in the light path between the light emitting element and the light receiving element, such as a water tank or a drain pipe. To control a washing or rinsing operation by accurately detecting changes in turbidity of a washing liquid due to dirt falling from laundry, even if dirt is attached to the laundry.

Means for Solving the Problems In order to achieve the above objects, the washing machine control device of the present invention includes a drain valve driving means for controlling ON/OFF of a drain valve for draining liquid in the tank, and A light emitting element and a light receiving element are provided near the drain valve to detect the light transmittance of the liquid, and the drain valve is turned ON for a predetermined period of time during water supply for rinsing operation.
The light emitting device is configured to include a control means for determining a drive current of the light emitting element after the light emitting element is driven.

According to the present invention, the drive current for the light emitting element is determined during the water supply during the rinsing operation, so even if the inner wall near the drain valve is dirty, if a large current is passed through the light emitting element, it will be fixed even when the inner wall near the drain valve is not dirty. You will get the same output as .

EXAMPLE Hereinafter, an example in which the present invention is applied to a fully automatic washing machine will be described with reference to the drawings.

Figure 1 is an i-side view of a fully automatic washing machine. 1 is the outer frame, 2 is the water tray, 3 is the washing and dehydrating tank, and 6 is the stirring blade 4 during washing or rinsing, and the stirring blade 4 during dehydration. This is a power switching mechanism for switching the power of the washing/extracting motor 5 so as to rotate the washing/extracting tank 3. 7 is air to generate pressure corresponding to the water level, and 9 is air! An air hose for transmitting the pressure generated in the sif to the water level detection means 8, 10 a water receiver and a drain valve for discharging the liquid in the tank 2 to the outside, 11 a drain hose, and 12 a water receiver for receiving tap water. is tank 2
This is a water supply valve for supplying water to the inside.

13 is a transmittance detection part for detecting the transmittance of the liquid in the tank 2, and as shown in FIG.
3a and a light receiving element 13b.

Next, FIG. 3 shows the main part configuration of a fully automatic washing machine.

In the figure, 14 is an input means for setting which process of washing, rinsing, and dehydration is to be performed and the water level, etc.; 15;
8 is a display means for informing the user of the contents set by the input means 14 and the progress of washing, 8 is a water receiver that detects the water level in the tank 2 and generates an electric signal;
17 is a bidirectional thyristor for driving the washing and dewatering motor 5, 18 is a bidirectional thyristor for driving the water supply valve 12, 19 is a bidirectional thyristor for driving the drain valve 1o, and 20 is a bidirectional thyristor for driving the water supply valve 12. 21 is a commercial power source, 21 is a power switch, 22 is a water receiver is a transmittance detector for detecting the degree of contamination of the liquid in tank 2, and 23 is a transmittance detector that calculates the maximum value of the output signal of the transmittance detector 22 within a predetermined time. 24 is a peak hold circuit for inputting the output signal of the peak hold circuit 23 into an A/D converter section, A/D converting it, and operating each process of washing, rinsing, and dehydration based on the data. A microcomputer (hereinafter referred to as a microcomputer) is a control means. Further, 25 is a non-volatile memory. FIG. 4 shows an example of the transmittance detector 22 and the peak hold circuit 23. 22a is a constant current source for receiving signals from the PWM circuit and the D/A converter from the microcomputer 24 and passing a constant current to the infrared light emitting element 13a;
b and 22d are resistors, and 22c is a signal from the microcomputer 24 that turns on/off the current flowing through the infrared light emitting element 13a.
This is a transistor that controls the In addition, the peak hold circuit 23 is connected to transistors 23a and 23d, an electrolytic capacitor 23b, and a resistor 23c.
We will explain the measurement of times. The cycle of the microcomputer 24 is Tb
(for example, 1 second), the transistor 22c is ONI for a period of Ta (for example, 0.01 second), and a current is caused to flow through the infrared light emitting element 13a. At this time, the base potential v1 of the transistor 23a changes as shown in FIG. 5 in accordance with the transmittance of the transmittance detector 13. The predetermined time T of the voltage value for each Tb. (
For example, in order to detect the maximum value for 10 seconds), the input is input to the A/D converter of the microcomputer 24 via the peak hold circuit 23, and the transistor 23d is turned on to detect the maximum value for the next TC. Immediately before the output voltage v0 of the peak hold circuit 23 is set to Ov, vo is measured by A/D conversion. In this way, n times (n is a natural number) during the predetermined time To
By taking the maximum value of vl, it is possible to eliminate the influence of bubbles generated during washing.

Next, washing control according to an embodiment of the present invention will be explained with reference to FIGS. 6 and 7. 1. Figure 6 is a graph showing the change in the output voltage vo from the start of washing. Curve A in the figure shows the curve when the degree of dirt on the laundry is small, curve B in the figure shows the curve when the degree of dirt is medium, and curve C in the figure shows the change in the output voltage vo from the start of washing. is when the degree of contamination is large. here,
Focusing on the saturation time t8, which is the time at which the output voltage vo does not change (for example, the time in a meeting where the change amount for 2 minutes is 0.1 V or less twice), and the output voltage v8 at the time of saturation, , as shown in Figure 6, when the laundry is heavily soiled (curve C), the saturation time is tfLC, which is long, and the output voltage at saturation is vlIo, which is low; When the dirt is small (curve A), the saturation time is tea and short;
The output voltage at saturation increases with vs&. Next, the flow of washing control will be explained with reference to FIG. First, in step 100, the microcomputer 24 reads out the PWM data for determining the drive current 11 of the light emitting element 13a and the output voltage vw when the inside of the transmittance detection section 13 is clear water, from the nonvolatile memory 25.
In step 101, PWM data is output and the light emitting element 13
A is controlled to flow a constant current 11, and in step 102, the water supply valve 12 is turned on to supply water to a predetermined water level, and in step 103, the stirring blade 4 is rotated to start the washing operation. In step 104, the output voltage ■. It is considered to be saturated if the change in 2 minutes becomes less than 1V twice in a row. Then, in step 105, the time at saturation 1 from the start of the washing operation is set to saturation time t.
8, and the output voltage at saturation is vll, tg and VB
The washing time is determined based on the value of /'vw. Here v
The reason why the vwO ratio is set to 8 is simply the output voltage v at saturation.
If you judge the degree of cloudiness of the washing liquid only by the value of Il, it will be possible to detect dirt that has fallen from the laundry, detergent that remains undissolved during washing, and water.
If the inner wall of the drain pipe in the transmittance detection unit 13 becomes dirty due to mosquitoes or the like, the output voltage vo will always be low, and it will be determined that the laundry is heavily soiled, resulting in a longer washing time. Therefore, in order to always accurately determine the degree of cloudiness of the washing liquid, the ratio of the output voltage VB at saturation to the output voltage VW at clean water is determined.

Next, how to obtain the output voltage vw during fresh water will be explained with reference to FIGS. 8 and 9. wash.

During the series of rinsing and dehydration processes, the inside of the transmittance detection unit 13 becomes clean water during the three times of water supply: washing, first rinsing, and second rinsing, as shown in Figure 8. be. However, during washing water supply, if the user adds detergent before starting washing, a concentrated detergent liquid will flow into the transmittance detection unit 13 with the first washing water supply, and the light transmittance will increase. As the voltage decreases, the output voltage vl also decreases. On the other hand, during the rinsing water supply, the inside of the transmittance detection unit 13 becomes clear water, but in the second rinsing water supply, a softening agent is often added, and the liquid is slightly cloudy. Therefore, how to determine the output voltage (2) when the transmittance detection unit 13 is filled with clean water during the first water supply for rinsing will be explained based on the flowchart of FIG. 9. The microcomputer 24 turns on the water supply valve 12 in step 160 to supply water at the lowest water level 1, and in step 161 the water supply valve 12 is turned on.
Turn on for 3 seconds to drain water. This is because the previous step is dehydration, and the bubbles generated during dehydration are discharged from the transmittance detection section 13. Next, in step 162, the drive current of the light emitting element 13a is determined to be appropriate so that the output voltage vl always changes in the active region. The transmittance detection unit 1 transmits PWM data that determines .
3 is set when the water is clear, and the output voltage vl at that time is set to 7. Then, in step 153, all determined data is written into the non-volatile memory 25 for use during the next washing. Subsequently, after water is supplied at a predetermined water level 1 in step 154, rinsing control is entered in step 155.

Effects of the Invention As described above, according to the present invention, the drive current for the light emitting element is determined after the water is once drained during the first rinsing water supply, and the sensor output voltage at that time is set as the output voltage vw during fresh water. Even if a large amount of foam accumulates in the transmittance detection section during the dewatering process in the previous step, all of it can be discharged and a highly accurate output voltage vw during clean water can be obtained. As a result, in washing control, it is possible to accurately detect the degree of turbidity of the washing liquid with respect to clean water when the sensor output voltage is saturated, and it is possible to perform an appropriate washing operation according to the degree of dirtiness of the laundry. ! In addition, each time the driving current of the light emitting element and the output voltage VW during fresh water are determined, they are stored in the non-volatile memory, so for example, even if the power outlet is unplugged, there will be no adverse effect on the next washing. Furthermore, since the drive current of the light emitting element is determined once for each wash,
Even if the inner wall of the transmittance detection section is soiled with water stains, undissolved detergent, etc., the degree of soiling of the laundry can be accurately detected by passing a large amount of current according to the degree of soiling.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a fully automatic washing machine according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of a transmittance detection section according to an embodiment of the present invention, and FIG.
The figure is a block diagram of the main parts of a fully automatic washing machine according to an embodiment of the present invention, FIG. 4 is a circuit diagram of a transmittance detection button and a peak hold circuit according to an embodiment of the present invention, and FIG. 5 is a circuit diagram of a transmittance detection button and a peak hold circuit according to an embodiment of the present invention. FIG. 6 is a timing chart of an embodiment of the present invention. FIG. 6 is a characteristic diagram of a button during washing of an embodiment of the present invention. FIG. 7 is a flow chart showing the operation of an embodiment of the present invention during washing. FIG. 9 is a flowchart showing the rinsing operation of an embodiment of the present invention. 2...Water receiver is a tank, 10...Drain valve, 1
3...Transmittance detection section, 13. ...... Light emitting element, 13b... Light receiving element, 19...
Drain valve driving means, 22...Transmittance detector, 24
...Microcomputer.

Claims (1)

[Claims] A drain valve driving means for controlling ON/OFF of a drain valve for draining the liquid in the tank, and a light emitting element and a light receiving element provided near the drain valve to detect the transmittance of light of the liquid in the tank. Then, the drain valve is turned on for a predetermined period of time during water supply for rinsing operation.
A control device for a washing machine, comprising a control means for determining a drive current for the light emitting element after the light emitting element is driven.